In the projection system, since the position of the viewer is relatively fixed, it is desired that the projected light of the image projected onto the screen by the projection system is only reflected to the viewer field, and not reflected to other invalid areas, so as to improve the efficiency of the projection system and then improve the brightness of the image on the screen viewed by the viewer. In addition, it is desired to reduce the reflected light, which is on the screen and observed by the viewer, reflected by the stray light instead of being reflected by the image of the projection system, thereby improving the contrast of the projection system.
In the related art, it has been proposed to increase the microstructure on the surface of the screen to meet the above two requirements. However, all of these microstructures use physical (such as shot peening) or chemical (such as corrosion) methods to form random microstructures on the surface of the screen, and although emergent light can have a certain emergent angle statistically by a certain control method, it is impossible for such microstructure to control the stray light not to be emitted to the viewer field, resulting in a lower contrast of the projection screen.